Fluid railway side bearings

ABSTRACT

Rocking motion of a railroad car body, supported on a truck bolster, is reduced and absorbed by a cylinder and a plunger side bearing assembly arranged on opposite sides of the bolster center plate. The cylinders have chambers filled with liquid in communication with one another through restricted orifices and an interconnecting conduit.

United States Patent 1 Zupez 1 Jan. 30, 1973 [54] FLUID RAILWAY SIDE BEARINGS FOREIGN PATENTS OR APPLICATIONS 1 lnvemofl v" Saint Louis, 620,144 3/1949 Great Britain ..267/l41 [73] Assignee: Abex Corporation, New York, NY.

Primary Examiner-Gerald M. Forlenza 22 F l A 29 1969 I 1 1 ed Assistant Exam inerHoward Beltran PP N05 854,172 Att0rneyKinzer and Dorn [52] US. Cl. ..l05/l99 CB, 267/3, 308/138 [57] ABSTRACT [51] Int.Cl. ..B6lf 5/14,Fl6c l7/04,Fl6f9/10 58 Field of Search ..10s/199, I64, 199 CB; Rckmg of a ralmad car body Supported?" a 188/64 R; 248/10; 267/141, 3; 308/138 truck bolster, 1S. reduced and absorbed by a cylinder and a plunger side bearing assembly arranged on op- [56] References Cited posite sides of the bolster center plate. The cylinders have chambers filled with liquid in communication UNITED STATES PATENTS with one another through restricted orifices and an in- 2,705,118 3/1955 Beck ..248/l0 terconnecting conduit. 2,093,486 9/l937 Schoepf et al ..l0S/l99 3,439,63l 4/1969 Cope ..lO5/l99 X 2 Claims, 3 Drawing Figures PATENTED JAN 3 0 I975 SHEET 1 [IF 2 INVENTOR. JOHN A. ZUFEZ BY 12%.; w

ATTORNEYS PATENTEU JAN 3 0 I973 SHEET 2 BF 2 II/ /r/ MAX. STROKE-\ FIG.3

INVENTOR. JOHN A. ZUPEZ ATTORNEYS FLUID RAILWAY SIDE BEARINGS This invention relates to railroad equipment and in particular a means for absorbing and transferring energy produced by the rocking motion of the body of a railroad car supported on a truck bolster.

Railroad cars in motion may encounter a rocking action due to staggered rail joints. A wheel may be deflected as much as three-quarters of an inch or more. Thus, the truck and car body may lean to the left and then to the right, starting harmonic actions which can lift the wheel four inches off the track and result in a derailment. An angle of rock within is acceptable, but 11 is deemed critical if allowed to prevail for too much distance along the track.

The primary object of the present invention is to enable rocking motion to be retarded by apparatus which can be easily and inexpensively incorporated in existing car structures without alteration in standard geometry of the car. Another object of the invention is to as sociate bearing structure with the same apparatus, accomodating normal motion between the car body and the car truck. More specifically, it is an object of the present invention to interpose a cylinder and related plunger assembly between the frame of the car and the bolster of the car truck, one assembly on each side of the bolster center plate, the two assemblies being so interconnected that the energy of rocking motion may be both held to a minimum and absorbed and dampened quickly to an effective zero value, manifesting a quick return to a stable condition; and the plunger is so arranged as to constitute a bearing element.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, shown a preferred embodiment of the presentinvention and the principle thereof and what is now considered to be the best mode contemplated for applying this principle. Other embodiments of the invention embodying the same or equivalent principle may be made as desired by those skilled in the art without departing from the present invention.

In the drawings:

FIG. I is an end elevation, partly in section, of a car frame and truck incorporating the apparatus of the present invention;

FIG. 2 is a plan view of a cylinder and plunger assembly; and

FIG. 3 is a sectional view on the line 3-3 of FIG. 2.

Referring to FIG. I, a portion of a railroad car is shown in end elevation and partly in section, the car having a pair of wheels W travelling on rails R. The frame of the car, so much shown in FIG. 1, is identified by reference character 10, the car frame having a center plate 11 engaged with a related center plate 12 of the bolster 14 of the car truck. The bolster 14 has opposed ends supported resiliently by spring assemblies 15 which are part of the side frames 16 of the truck.

The rail system presents rail joints, and the spacing between the ends are staggered. In any event, the wheels in traversing the rail joints establish vibrations which are transmitted to the car frame 10 producing rocking motion which would be manifest in a seesaw action of the frame 10 relative to the bolster 14 as viewed in FIG. 1.

In accordance with the present invention this rocking motion is reduced and absorbed by a cylinder and plunger assembly 20, one such assembly being located on each side of the bolster center plate within the space between the upper side of the bolster and the underside of the car frame as shown in FIG. I. Inasmuch as each such assembly is identical, only one will be described in detail in connection with FIGS. 2 and 3.

The cylinder 21, FIG. 3, includes a base flange 22 having apertures 23 which accomodate bolts for securing the cylinder to the truck bolster. The cylinder includes a vertically extended circular wall 25 which defines a relatively large cylinder bore 26.

Associated with each cylinder is a plunger or piston 30 having a sleeve-like extension 31 of continuous circular form projecting into the bore of the cylinder. The sleeve of the cylinder is of substantially less radial dimension compared to the radius of the bore 26, and the concentric space between the bore and the plunger sleeve is filled by a continuous collar of elastomeric material 35 which may be synthetic urethane rubber, or the like. The elastomeric collar serves both as a seal and a return spring, as will be apparent from the description to follow.

The lower end of the plunger is spaced considerably from the opposed interior bottom wall 25W of the cylinder, resulting in a cylinder chamber 36 to be filled with liquid.

A washer 37 is welded to the lower end of the plunger sleeve. The diameter of the washer 37 is substantially the diameter of the cylinder bore 26, and a rubber O-ring 38 is fitted tightly in a corresponding groove in the periphery of the washer 37, the O-ring having a sliding seal fit with the cylinder bore 26. In the course of construction, the plunger 30 may be pressed in place to the position shown in FIG. 3, defining the chamber 36, whereafter the elastomer may be poured in place bonding the collar 35 to the walls of the cylinder bore 26 and to the exposed external wall 30W of the plunger sleeve. The O-ring 38 seals the chamber 36 so that no elastomer flows thereto during pouring.

The upper end of the plunger 30 projects beyond the top edge of the cylinder 21 and a flange 40 is provided at the free end of the plunger. As shown in FIG. 1, an appropriate wear plate 40A, depending upon the geometry at the underside of the car frame, is fastened to the car body bolster to establish engagement between the car frame and the upper end of the plunger 40. The plunger 40 may be made of austenitic man ganese steel and the wear plate of hardened steel. This represents ari ideal wear and anti-friction combination inasmuch as the mating surfaces form mirror-smooth finishes as they rub one on another in the course of accomodating relative motion between the car body and the car truck.

The chamber 36 of each cylinder is provided with a restricted orifice 45, FIG. 3, and leads to a port 46 in the cylinder base to which is threaded an adapter 47 having an external nipple 48. As shown in FIG. 1, a conduit 50 is joined to the nipple of each adapter so that two cylinder and plunger assemblies 20 have their chambers 36 in communication, through the conduit 50. Each chamber 36 and the interconnecting conduit are filled with an appropriate compressible fluid, preferably a compressible silicone oil.

The rocking motion of the frame having the seesaw characteristic mentioned above represents a see-saw amount-of energy which is to be absorbed to reduce and retard the amount of rocking motion. This rocking motion may be sufficiently severe as to establish the maximum stroke of the plunger into the cylinder chamber 36 as identified by legend and dotted lines in FIG. 3. The present unit can tolerate a nine-sixteenth inch deflection in 0.470 seconds, absorbing 120,000 inch pounds of energy. In any event, assuming a downward thrust imparted to one of the plungers 30 by the car frame, resulting in stressing the elastomeric collar 35, fluid in the chamber 36 of the corresponding cylinder is forced through the restricted orifice 35, by which a great deal of the energy of frame rocking is immediately dissipated by heat, and at the same time liquid is transferred to the chamber of the other cylinder thereby damping the motion of the car frame. If the car rebounds in the opposite direction, then transfer of liquid takes place again, and so on repeated until a stable condition is once again attained.

Most railroad cars are built with a standard side bearing occupying the position of the cylinder and the wear plates 40A of the present invention, and thus it will be seen that the apparatus of the present invention requires no change in truck or bolster configuration. The side bearing of the prevailing structure includes a roller which contacts a fixed member on the bolster of the car body, and as the car truck swivels in rounding curves the roller acts like a rolling pin. The clearance between the engageable parts of the standard side hearing is supposed to be maintained at one-eighth inch (minimum) or one-fourth inch (maximum) and this clearance represents rocking angle allowances.

The present apparatus also presents a bearing represented by the engaged surfaces of the plunger and the wear plate. The bearing structure which thus features in the present disclosure is of the constant contact type with a pre-load travel of one-fourth inch. This establishes side bearing pressure as an amount equal to the shear resistance of the elastomer and the compressibility of the fluid (silicone oil) in the cylinder cavity. The total stroke of the plunger is nine-sixteenth of an inch, and one-fourth inch of this stroke is to insure contact and pre-load pressure, leaving a working stroke of five-sixteenth inch. This means that even if the centrifugal load on the side bearing as thus constituted, when the cars round a curve, exceeds the resistance pressure (the plunger bottoms") the deflection would not exceed the safe limit of car tilt.

The washer 37 is a convenient means of enabling the elastomer to be cured without flowing into chamber 36, but other means may be used to accomplish this purpose in which event the washer 37 may be eliminated.

FIG. 3, phantom lines, shows the plunger 30 bottomed, and it will be noted that concavities 30C on the lower end of the plunger and concavities 22C at the interior of the cylinder bottom wall serve, at this time, to contain a volume of undisplaced fluid even though the plunger is bottomed to engage the bottom wall of the cylinder. Consequently there is no possibility of cavitation of vapor lock.

Hence, while I have illustrated and described a preferred embodiment of my invention, it is to be understood that this is capable of variation and modification.

I claim: 1. In a railroad car truck having a bolster member supported at opposite ends by springs, said springs being included as part of the side frames of the car truck, the bolster in turn supporting the frame member of the car for rocking motion relative to a center plate, means to absorb energy due to rocking motion of the car frame member and comprising: a pair of cylinders arranged between the members and secured to one of the members on opposite sides of the center plate, each cylinder having a bore, a plunger disposed in each cylinder and having a portion projecting outwardly thereof in engagement with an opposed bearing element on the opposed part of the other member, each plunger in the portion thereof disposed in the cylinder being of smaller radial dimension than the bore of the cylinder, a continuous elastomeric collar joining opposed wall surfaces of the plunger and the cylinder bore to seal the space therebetween and to resiliently support the plunger, the plunger normally projecting but part way into the cylinder so that the plunger has a lower end spaced from the interior bottom wall of the cylinder defining a chamber for liquid, the engagement of the plunger with the bearing element exerting a preload on the elastomeric collar, each chamber having an orifice therein, a conduit joining the orifices so that when one plunger is depressed through a working stroke by rocking of the car frame, liquid in the corresponding chamber is forced through the orifice and is transmitted to the orifice and chamber of the other cylinder, and at least one of the lower ends of the plunger and the interior bottom wall of the cylinder having a concavity therein so that when the plunger is bottomed to engage the interior bottom wall of the cylinder some liquid is undisplaced and is retained in said cavity.

2. Apparatus according to claim 1 wherein the preload limits the working stroke of the plunger to a fraction of an inch. 

1. In a railroad car truck having a bolster member supported at opposite ends by springs, said springs being included as part of the side frames of the car truck, the bolster in turn supporting the frame member of the car for rocking motion relative to a center plate, means to absorb energy due to rocking motion of the car frame member and comprising: a pair of cylinders arranged between the members and secured to one of the members on opposite sides of the center plate, each cylinder having a bore, a plunger disposed in each cylinder and having a portion projecting outwardly thereof in engagement with an opposed bearing element on the opposed part of the other member, each plunger in the portion thereof disposed in the cylinder being of smaller radial dimension than the bore of the cylinder, a continuous elastomeric collar joining opposed wall surfaces of the plunger and the cylinder bore to seal the space therebetween and to resiliently support the plunger, the plunger normally projecting but part way into the cylinder so that the plunger has a lower end spaced from the interior bottom wall of the cylinder defining a chamber for liquid, the engagement of the plunger with the bearing element exerting a pre-load on the elastomeric collar, each chamber having an orifice therein, a conduit joining the orifices so that when one plunger is depressed through a working stroke by rocking of the car frame, liquid in the corresponding chamber is forced through the orifice and is transmitted to the orifice and chamber of the other cylinder, and at least one of the lower ends of the plunger and the interior bottom wall of the cylinder having a concavity therein so that when the plunger is bottomed to engage the interior bottom wall of the cylinder some liquid is undisplaced and is retained in said cavity.
 1. In a railroad car truck having a bolster member supported at opposite ends by springs, said springs being included as part of the side frames of the car truck, the bolster in turn supporting the frame member of the car for rocking motion relative to a center plate, means to absorb energy due to rocking motion of the car frame member and comprising: a pair of cylinders arranged between the members and secured to one of the members on opposite sides of the center plate, each cylinder having a bore, a plunger disposed in each cylinder and having a portion projecting outwardly thereof in engagement with an opposed bearing element on the opposed part of the other member, each plunger in the portion thereof disposed in the cylinder being of smaller radial dimension than the bore of the cylinder, a continuous elastomeric collar joining opposed wall surfaces of the plunger and the cylinder bore to seal the space therebetween and to resiliently support the plunger, the plunger normally projecting but part way into the cylinder so that the plunger has a lower end spaced from the interior bottom wall of the cylinder defining a chamber for liquid, the engagement of the plunger with the bearing element exerting a pre-load on the elastomeric collar, each chamber having an orifice therein, a conduit joining the orifices so that when one plunger is depressed through a working stroke by rocking of the car frame, liquid in the corresponding chamber is forced through the orifice and is transmitted to the orifice and chamber of the other cylinder, and at least one of the lower ends of the plunger and the interior bottom wall of the cylinder having a concavity therein so that when the plunger is bottomed to engage the interior bottom wall of the cylinder some liquid is undisplaced and is retained in said cavity. 